Alternator

[rezsst]

Stupid question. Im having problems with voltage, im 12v at battery and 15.5 at alternator. Should be 14.4 at alternator, its a remanufactured from China. Can i run a line directly to the battery from a alternator. Fused.

Just got this truck titled as a 87 but its actually a 82 k30 454/465/205 d60/14bolt. My other is a 79 k5 ive been driving for years but needed something to pull our camper.

 

[nutt7]

Yes, you can run a wire from the alternator to the battery...there should actually already be an 8awg (maybe) one there...and maybe a smaller one to the firewall depending on the set-up. Where is the alternator output currently going? Also, once the alternator warms up, the voltage should drop too.

 

[Fordum]

Check your grounds. High voltage at the alternator usually means its missing a ground reference.
However, in this case, it could be caused by not having a load. A voltage regulator can only do so much. Without a load on the output, the voltage can float fairly high.
There should be a large red wire on the back of the alternator or in a harness depending on what model you have. That wire has to wind up at the positive terminal of the battery. If it seems to be hooked up, check the battery clamp its self. Where the red wire is connected, may be physically connected but not electrically connected due to corrosion.

 

[diesel4me]

The wiring from the factory ,has a thick red wire on the stud at the back of the alternator--from there it runs all the way to the main harness behind the engine,where it branches off in two directions,one goes to the starter solenoid where the positive battery cable and fusible link wires go ,that power the cab--and the other goes to the junction block up near the brake booster,then on to the fuse box..
If the wire is faulty between the alternator and the starter solenoid or junction block it can reduce the amount of amps & volts that get back to the battery..

I ran a short length of 8 gauge wire right to the battery positive to the alternator stud on my diesel pickup,the battery on the passenger side was only about a foot away from the alternator..this reduces the amount of voltage drop ,from the factory wiring taking such a long route before the charge gets back to the battery..
I noticed an improvement in the volt gauge reading and brighter headlamps and faster wipers after adding that extra wire..truck is almost 40 years old so I'm sure the original harness has some corrosion..